Well drilling



Pris w 3951 G. D. PRlEsTMAN ETAL 2,548,616

WELL DRILLING Filed Feb. 2, 1948 /a//oe zenders w @Eig Z.

Patented Apr. 10, 1951 OFFICE WELL DRILLING George Dawson Priestman, Tulsa, Okla., and Gerald Priestman, Elizabeth, N. J.

Application February 2, 1948, Serial No. 5,776

The present invention relates to well drilling equipment useful for wells generally but primarily oil wells and in particular to equipment and method for continuously or semi-continuously feeding substantially rigid metal pipe of any length into a well either as a drilling string or casing or both.

The equipmentherein is compact so that it may be mounted portably and allows replacement of the heavy cumbrous drilling equipment in common use such as a derrick without sacrifice of the normal utility thereof. Thus the present equipment lends itself to additional well drilling operations such as ordinary prospecting, Vand small hole drilling while being of equal utility `for ordinary well drilling.

In its broadest concept, long lengths of metal pipe brought up to the well either in a coil or in separate lengths which may be welded together in a continuous string while lying flat on the ground in the neighborhood of the well bore,

pipe, if already in a proper arc as unwound from a coil, may be passed directly to the pipe straightening machine and thence into the well without being rst bent.

Thus, proceeding according to the present invention, long lengths of pipe are assembled on the ground through welding-made part of the drilling mud circuit and continuously fed into the wellas drilling operations proceed with circulation of mud therethrough by continuously passing the pipe into the well, straightening the metal in a pipe straightener at the top of the well, or the pipe, if brought up in a continuous coil, is similarly made part of the well drilling mud circuit and fed into the well through the pipe straightener. In either or both instances the pipe,` unreeled from the coil or brought up from the ground to the mouth of the well may be rst passed through a pipe bending machine and thence through the pipe straightener after a proper arc is formed, if necessary. In this invention the drill pipe and bitdriving mechanism or motor are non-rotating, and only the bit may be rotating or reciprocating in contrast to conventional drilling procedures in which the power 8 Claims. (Cl. Z55-4) mechanisms at the surface rotate the drill pipe which in turnV rotates the bit.

Reference is made to the accompanying drawing showing somewhat diagrammatically the drill rig assembly of the present invention.

`Fig. 1 shows the pipe mounted as a coil on a reel;

Fig. 2 shows handling of pipe such as by Welding into long lengths up on Vthe ground;

Fig. 3 is a section through the reel showing the coils of pipe as mounted on the reel core; and l Fig. 4 is a modied detailed view of an end of the pipe and casing and drilling motor showing the use of concentric piping, comprising the casing and drilling string.

As will be noted, the several unitfg` are shown mounted on base elements II) and III which may be pontoons, or which may be portably lifted onto a pontoon or portable truck, or the same units themselves may be provided with removable or securely anchored wheels so as to make them readily portable. The left hand pontoon of Fig. 1, Ill', is mounted over a well II into which substantially rigid metal pipe string I2 is to be fed. At the lower end ofthe string is" conventionally xed a fluid pressure or other type of motor I3 to which is conventionally attached the drill bit I 4. The bent pipe I2 is fed into the pipe straightener I5 rigidly mounted on the pontoon I0. v v

The pipe straightener I5 comprises several roller elements I6 driven by almotor Il. As is conventional in pipe straighteners such rollers dene at their adjacent peripheries a passageway for a straight pipe such that any pipe passed therethrough is rolled or ironed by rotation of rollers I5 into straight lengths. While this type of straightener is described as an example, other types of pipe straighteners known in the art, such as those employing heat for straightening the pipe, may be used as desired. From the rollers II the straightened pipe I2 passes down into the through which pipe l2, as unwound from reel I3,

may be caused to pass for bending into a desired arc for feeding from coil form to the pipe straightening unit I5. The pipe benders 28 comprise a series of roller elements '29 adjustable in relative position to each other to. define an arc f such that pipe I2 passing through the space` defined at the adjacent peripheries of cooperative rollers 29 is bent gradually` by each roller 23, 29a, 29h, etc., passing out of the device bent to the desired arc of curvature.

The core element 22 of the reel I3 is bored at 35 or formed as hollow pipe construction comprising the axis thereof from both or either end and: is radially joined by a duct 3| to which the end of the coiled pipe I2 is fastened or coupled in a. fluid type manner as with a pipe union, welded or otherwise. As shown, a pipe 32, carrying; drilling fluid recycled from the well or from other source or carryingk motor energizing fluid of thev character of gas or liquid, or wire if an electric driving motor is used, is coupled to the duct 30 in a fluid tight manner at 33 by means of a stuffing gland or, other known construction allowing the uid circuit tov lne-completed through the rotatablecore 22 and` thence through the pipe I2 connected thereto.

Power fluid or drilling mud issupplied to the pipe.- 3-2- throught pump 34. Fluid supplied to the pump 34 at the suction end thereof may enter from. outside the system through pipe .t5 or may be recycled drilling uid coming from the well throughzpipe 36. Fluid passing up from the well iI- may be rst sentto an. intermediate settling bas-in 3l' and thence through a lter 38 before being recycled tothe pump 34 1oyway of pipe 3E.

I-noperation of thisY device the coiled pipe on reelt8 carries power fluid and/ or lubricant sent through` it through the entire length by way of pump 3ft, pipe 32, stuiiing gland 33', core duct 33, andconnecting pipe 3|. The huid passes into the well, driving the drilling motor i3 which rota-tes, reciprocates or oscillates the drill bit I4 lubricating the same and carrying away the cuttings while applyingdesired hydrostatic pressureatthebottom ofthe well. The drilling mud lea-ving the well together with the cuttings are firstfsettled in basin 3'! and then passed through lter 38' and is iina-lly recycled to the pump 3.. The drilling iluidmay bev analyzed for evidence of oil and rock types at any suitable point such as: at the basinl 3?.

At the beginning ofV operations, drilling fluid or power medium for the drilling motor may be supplied; through duct and the introduction of fluid may beY entirelythro'ugh 35, as desired throughout drilling operations. It will be understoodtha-t any known power medium, gas or liquid, may be used, or for an electric motor only wires will be needed inV which, case Vthe fluid acts only as a lubricant. Simultaneously, pipe is fed by uncoilingA the pipe I2 from the reel I8 as rotated at desired rate by motor 24. If desired, the pipe I2V is sent throughv the pipe bender unit 28 asdriven by motor 39 in synchronization with therateof movement of the pipe therethrough.

and pipe straightener, as described'.

The bent pipe is then fed through the pipe straightening unit I5 from whence it passes down into the well as straight substantially rigid metal pipe. The controlled rate of feed through the bending and straightening units and the uncoiling from the reel acts to assist in applying and relieving pressure on the bit, but these units may be further constructed with conventional braking elements (not shown) as desired to facilitate such control.

When the casing is to be withdrawn the operation is reversed and the metal pipe passing in reverse direction through the pipe bender unit 28 may be fed back onto the reel I8 in coil form. After one length of pipe has been used up the end of the pipe I2 may be unconpled from pipe 3| and a new reel of pipe substitututed for reel I8 and the end thereof joined to pipe l2 as by welding or otherwise.

In the modication shown in Fig. 2 pipe I2 is constructed of a single straight long pipe length assembled as such generally horizontally on the ground neighboring the well as by welding short lengths of suitable portable pipe lengths. One end of the straight pipe length is then coupled at 40 to the pressure side of the pump 34 from whence it is fed into a pipe bending unit 28 and thence through pipe straightener i5 passing down into the well. The power and mud circuit is otherwise the same as explained in Fig. l above. VIn this instance, as the pipe is fed into the well, the pump mounted on the pontoon itis moved closer to the well as the pipe length is used up. After using up an assembled pipe length a new long ground-assembled pipe length is welded to the end of the pipe i2 and coupled to the pump 34 at 40 the pump being moved to the proper position therefor and the operation continued.

While this invention is admirably adapted to4 small hole drilling, because the equipment is readily portable, any diameter size pipe may be used. In the case of large size pipe, it is usually preferable, rather than coiling the same, to weld, screw or otherwise join lengths of pipe on the ground and thence by means of a bender unit 28 followed by straightener unit I5 the pipe may be caused to enter the ground at any desired angle, normally vertically.

It will be apparent that, since various sizes of pipe may be used, double pipe may be fed into the ground in concentric relationship. The larger pipe may desirably act as casing and the inner pipe as a drill string, such as shown in detailed Fig. 4. As shown in this detail, the casing may be perforated, with suitably spaced holes, to allow passage of lubricating iluidbe-v tween the casing and rock formation. In such application the pipe lengths are preferably assembled on the ground and both fed substantially c'oncentrically through the pipe benders It is possible to feedr smaller sizes of concentric pipe in pre-assembled coil form also. Various pipe sizes are;- contemplated, ranging from 1" to 3 for drilling string and larger for casing.

The motor I3 may be of any known type, such as hydraulic turbine` or reciprocating or oscillatingi typeL operated by the drilling mud or other power iiuid and electric motors may alsobe used. It is substantially rigidly suspended and supported against rotation by the substantially rigid pipe i2 but may be further braced against the rotary torque by conventional means as known inthe art.

As thus shown, drilling apparatus is taught, adapted to be portable and highly useful for exploratory purposes, using a single straight or coiled pipe length, or any number of pipe lengths welded together for conventional well drilling.

By ordinary metal pipe as the term is used herein will be understood the conventional steel pipe used in oil well drilling which, while it has a certain inherent strength, flexibility and rigidity as to require application of great force to bend and straighten the same as proposed herein, is critically distinguished from such pipe as rubber hose which may be relatively characterized as ilabby and flimsy and neither has comparable utility for well drilling with the metal pipe nor would such rubber pipe require the use of bending and straightening devices as proposed herein.

Various modifications of the coil construction, the reel, the pipe bender and straightener, the pump, motor and means for purifying the drilling iiuid will occur to those skilled in the art. It will also be apparent that any devices known and used in the drilling of wells which are lowered into the hole on conventional pipe or cable for obtaining cores, determining structures or bit locations may be applied to the nonrotating pipe as described herein. It is intended that the description be regarded as exemplary and not limiting and the invention be interpreted as broadly as dened in the claims.

We claim:

l. A well drilling unit comprising a motor, a well drilling bit connected to the motor for actuation thereby, means for raising and lowering said motor and bit in a well bore comprising a string of drill pipe, said pipe being characterized by being a single uninterrupted length of substantially rigid metal well drilling pipe capable of being bent beyond its elastic limit, means for feeding said drill pipe from a position wherein the pipe is normally disposed on the surface of the ground neighboring said well to the substantially vertical position of the pipe within the well wherein the drilling requires application of curvature to said pipe beyond the normal elastic limit thereof,- said feeding means comprising a pipe curving means.

2. A well drilling rig for feeding a long continuous integral string of substantially rigid metal drill pipe requiring bending beyond the elastic limit of said pipe to form an arc to feed the pipe from a position on the ground adjacent the well to the substantially vertical position of the pipe wherein the pipe enters the well in the drilling thereof, having a drilling motor mounted on the inner end of said pipe 'within the well and a drilling bit mounted on said motor for actua-y tion thereby, comprising a pipe bender mounted adjacent said well through which the pipe is continuously fed, said pipe bender adapted to bend said pipe beyond the elastic limit thereof to form an arc suitable for entering said well from the position of the pipe on the ground, and a pipe straightener mounted above the well bore through which the bent pipe passes for continuously straightening said bent pipe and feeding the same into the well in the drilling thereof.

3. The drilling rig as defined in claim 1 wherein the outer end of the pipe is bent beyond the elastic limit in a coil about a reel and then passed to said pipe feeding means.

4. The drilling rig as defined in claim 1 having means for continuously passing drilling fluid into the outer end of said pipe.

5. The drilling rig as defined in claim 1 wherein the pipe comprises two pipes, a larger diameter pipe and a smaller diameter pipe disposed one within the other.

6, The drilling rig as dened in claim 2 Wherein the outer end of the pipe is bent beyond the elastic limit in a coil about a reel and then passed to said pipe feeding means.

7. The drilling rig as dened in claim 2 having means for continuously passing drilling uid into the outer end of said pipe.

8. The drilling rig as defined in claim 2 wherein the pipe comprises two pipes, a larger diameter pipe and a smaller diameter pipe disposed one within the other.

GEORGE DAWSON PRIESTMAN. GERALD PRIESTMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 287,444 Korner Oct. 30, 1883 1,245,274 Riley Nov, 6, 1917 2,013,070 Sheridan Sept. 3, 1935 2,056,471 Krall Oct. 6, 1936 2,292,126 Isley Aug. 4, 1942 2,336,338 Zublin Dec. 7, 1943 2,453,038 Rossmann Nov. 2, 1948 FOREIGN PATENTS Number Country Date 421,562 Germany Nov. 13, 1925 

